1. Technical Field
Embodiments of the present invention relate to a mounting structure for a front pillar trim accommodating an airbag and having an assist grip.
2. Description of Related Art
A vehicle main body includes side walls (e.g., doors and body side panels), a roof panel arranged above the side walls, and pillars supporting the roof panel. The pillars include a front pillar situated in a front portion of the vehicle. Since the major portion of the front pillar is formed of a metal plate-like member (e.g., a steel plate), a front pillar trim covering the vehicle inner side of the front pillar is provided. The front pillar trim constitutes the inner wall of the vehicle interior, and, like other trim members, is formed through a combination of an appropriate synthetic resin material, a textile material, etc. Thus, the front pillar trim has a design function of forming the vehicle inner wall as a smooth surface and a function of protecting an occupant at a time of collision of the vehicle.
The vehicle may be provided with an airbag device generally referred to as a curtain airbag for protecting the occupant at the time of collision of the vehicle. The airbag device stores a folded airbag along the front pillar and roof side rail. Based on an output from a collision detection sensor mounted to the vehicle, an igniter (ignition device) operates, and an inflator (gas generator) generates gas, causing the airbag to be inflated by the gas to develop in a curtain-like fashion along the side surface of the vehicle interior. When the airbag on the inner side of the front pillar trim expands, the airbag pushes away a rear end edge portion of the front pillar trim by an expansion pressure, and forms along the side wall of the vehicle interior from a gap between the front pillar and the front pillar trim.
An assist grip that may be grasped by the occupant at the time of getting in or out of the vehicle may be attached to the front pillar. The assist grip is fastened to the front pillar, which is formed of a rigid material in order to ensure a desired level of rigidity. The front pillar trim is held between the assist grip and the front pillar, and is firmly fixed in position. Accordingly, at the time of development of the airbag, the gap between the front pillar trim and the front pillar is not easily generated, and there is a fear of the airbag not being smoothly inflated and developed.
Japanese Laid-Open Patent Application No. 2000-108826 discloses a known pillar trim mounting structure. In the front pillar trim of the structure, an easy-to-rupture portion is formed around a portion where upper and lower ends of the assist grip are fastened. The easy-to-rupture portion is ruptured by the expansion pressure of the airbag, and causes a part of the front pillar trim to move toward a center of the vehicle interior, forming a gap between the front pillar and the front pillar trim.
However, the assist grip is fastened to the front pillar that is a rigid body, so that the front pillar trim can only move to a position where it is in contact with the inner peripheral surface of the assist grip. Thus, a sufficient gap is not formed between the front pillar and the front pillar trim, and there is a fear that the airbag won't smoothly inflate and form.
Depending on an order in which the easy-to-rupture portion is ruptured, a force is locally applied to the front pillar trim due to the expansion pressure of the airbag, and there is a fear of the front pillar trim being broken and scattered. Judging from a recent increase in the expansion pressure of airbag devices, such a concern may be more realistic. In some cases, a cover is attached to the surface of the front pillar trim in order to prevent breakage of the front pillar trim. However, adding the cover involves an increase in cost.
Thus, there has been a need for a mounting structure which suppresses interference between the front pillar trim and the assist grip at the time of expansion of the airbag to enable the airbag to smoothly expand and which can suppress breakage of the front pillar trim.